Cured in place liner having integral inner impermeable layer

ABSTRACT

A resin impregnated cured in place liner with an integral inner impermeable layer is provided. The liner is formed from a resin impregnable material having an impermeable layer bonded to one surface. The material is formed into tubular shape with the impermeable layer on the outside of the tube about a tubular forming member and continuously everted into the tubular forming device to place the impermeable layer on the inside. An outer impermeable film is placed about the inner tubular layer and may be impregnated with vacuum in the usual manner. Alternatively, the tubular resin impregnable material may be passed through a resin tank and impregnated with a curable resin prior to being wrapped with an outer impermeable layer. The impregnated liner is then suitable for pull-n-and-inflate which can be by steam in view of the integral inner impermeable layer of the liner.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of copending application Ser. No.10/703,814, filed Nov. 7, 2003.

BACKGROUND OF THE INVENTION

This invention relates to cured in place liners for trenchlessrehabilitation of existing conduits and pipelines, and more particularlyto a cured in place liner of a resin impregnable material with anintegral inner impermeable layer continuously manufactured in desiredlengths for trenchless rehabilitation of existing conduits by pulling inand inflating.

It is generally well known that existing conduits and pipelines,particularly underground pipes, such as sanitary sewer pipes, stormsewer pipes, water lines and gas lines that are employed for conductingfluids frequently require repair due to fluid leakage. The leakage naybe inward from the environment into the interior or conducting portionof the pipelines. Alternatively, the leakage may be outward from theconducting portion of the pipeline into the surrounding environment. Ineither case of infiltration or exfultration, it is desirable to avoidthis type of leakage.

The leakage in the existing conduit may be due to improper installationof the original pipeline, or deterioration of the pipe itself due tonormal aging, or the effects of conveying corrosive or abrasivematerial. Cracks at, or near pipe joints may be due to environmentconditions such as earthquakes, or the movement of large vehicles on theoverhead surface, or similar natural or man-made vibrations, or othersuch causes. Regardless of the cause, such leakages are undesirable andmay result in waste of the fluid being conveyed within the pipeline, orresult in damage to the surrounding environment and possible creation ofdangerous public health hazards. If the leakage continues it can lead lostructural failure of the existing conduit due to loss of soil and sidesupport of the conduit.

Because of ever increasing labor and machinery costs, it is increasinglymore difficult and less economical to repair underground pipes orportions that may be leaking by digging up the ex sting pipe andreplacing the pipe with a new one. As a result, various methods havebeen devised for the in place repair or rehabilitation of existingpipelines. These new methods avoid the expense and hazards associatedwith digging up and replacing the pipe or pipe sections, as well as thesignificant inconvenience to the public during construction. One of themost successful pipeline repair or trenchless rehabilitation processesthat is currently in wide use is called the Insituform® Process. TheInsituform Process is described in detail in U.S. Pat. No. 4,009,063,No. 4,064,211 and No. 4,135,958, the contents of which are allincorporated herein by reference.

In the standard practice of the Insituform Process an elongated flexibletubular liner of a felt fabric, foam or similar resin impregnablematerial with an outer impermeable coating that has been impregnatedwith a thermosetting curable resin is installed within the existingpipeline. In the most widely practiced embodiment of that process, theliner is installed utilizing an eversion process, as described in the'211 and '958 Insituform patents. In the eversion process, radialpressure applied to the interior of an everted liner presses it againstand into engagement with the inner surface of the pipeline as the linerunfolds along the length of the pipeline. The Insituform Process is alsopracticed by pulling a resin impregnated liner into the conduit by arope or cable and using a separate fluid impermeable inflation bladderor tube that is everted within the liner to cause the liner to cureagainst the inner wall of the existing pipeline. Such resin impregnatedliners are generally referred to as “cured-in-place-pipes” or “CIPPliners” and the installation is referred to a CIPP installation.

Conventional cured in place flexible tubular liners for both theeversion and pull-in-and-inflate CIPP installations have an outer smoothlayer of relatively flexible, substantially impermeable polymer coatingin its initial state. The outer coating allows a resin to be impregnatedinto the inner layer of resin impregnable material, such as felt. Wheneverted, this impermeable layer ends up on the inside of the liner withthe resin impregnated layer against the wall of the existing pipeline.As the flexible liner is installed in place within the pipeline, thepipeline is pressurized from within, preferably utilizing an eversionfluid, such as water or air to force the liner radially outwardly toengage and conform to the interior surface of the existing pipeline.Cure of the resin is initiated by introduction of hot curing fluid, suchas water into the everted liner through a recirculation hose attached tothe end of the everting liner. The resin impregnated into theimpregnable material then cures to form a hard, tight fitting rigid pipelining within the existing pipeline. The new liner effectively seals anycracks and repairs any pipe section or pipe joint deterioration in orderto prevent further leakage either into or out of the existing pipeline.The cured resin also serves to strengthen the existing pipeline wall soas to provide added structural support for the surrounding environment.

When tubular cured in place liners are installed by thepull-in-and-inflate method, the liner is impregnated with resin in thesame manner as in the eversion process and pulled into and positionedwithin the existing pipeline in a collapsed state. In a typicalinstallation, a downtube, inflation pipe or conduit having an elbow atthe lower end is positioned within an existing manhole or access pointand an everting bladder is passed through the downtube, opened up andcuffed back over the mouth of the horizontal portion of the elbow andinserted into the collapsed liner. The collapsed liner within theexisting conduit is then positioned over and secured to the cuffed backend of the inflation bladder. An everting fluid, such as water, is thenfed into the downtube and the water pressure causes the inflationbladder to push out of the horizontal portion of the elbow and cause thecollapsed liner to expand against the interior surface of the existingconduit. The eversion of the inflation bladder continues until thebladder reaches and extends into the downstream manhole or second accesspoint. At this time the liner pressed against the interior surface ofthe existing conduit is allow to cure. Cure is initiated by introductionof hot curing water introduced into the inflation bladder in much thesame manner as the recirculation line tied to the end of the evertingbladder to cause the resin in the impregnated layer to cure.

After the resin in the liner cures, the inflation bladder may be removedor left in place in the cured liner. Both the pull-in and inflate methodas well as the eversion method typically require man-access torestricted manhole space on several occasions during the process. Forexample, man-access is required to secure the everting liner or bladderto the end of the elbow and insert it into the collapsed liner.

Regardless of how the liner is to be installed a curable thermosettingresin is impregnated into the resin absorbent layers of a liner by aprocess referred to as “wet out.” The wet-out process generally involvesinjecting resin into resin absorbent layers through an end or an openingformed in the outer impermeable film, drawing a vacuum and passing theimpregnated liner through nip rollers as is well known in the liningart. A wide variety of resins may be used, such as polyester, vinylesters, epoxy resins and the like, which may be modified as desired. Itis preferable to utilize a resin which is relatively stable at roomtemperature, but which cures readily when heated with air, steam or hotwater, or subjected to appropriate radiation, such as ultra-violetlight.

One such procedure for wetting out a liner by vacuum impregnation isdescribed in Insituform U.S. Pat. No. 4,366,012. When the liner hasinner and outer impermeable layers, the tubular liner may be suppliedflat and slits formed on opposite sides of the flattened liner and resininjected and on both sides as described in the '063 Patent. Anotherapparatus for wetting out at the time of installation while drawing avacuum at the trailing end of the liner is shown in U.S. Pat. No.4,182,262. The contents of each of these patents are incorporated hereinby reference.

Recent efforts have been made to modify the pull-in and inflate methodto utilize air to evert a bladder into the pulled-in liner from aproximal access point. When the everting bladder reaches the distalaccess point, steam is introduced into the proximal access point toinitiate cure of the resin impregnated into the resin impregnable layer.This process offers the advantage of faster cure due to the increasedenergy carried by the steam as the curing fluid. However, the processstill requires eversion of a bladder into the pulled-in impregnatedliner. Efforts to avoid this step of everting the bladder into thepulled-in liner include performing the eversion step above ground. Forexample, in U.S. Pat. No. 6,270,289, the process includes everting acalibration hose into a flat-lying lining hose above ground prior topulling the hose assembly into the existing conduit. This process avoidsthe eversion below grade, but is severely limited into the length oflining that can be laid out above ground prior to pulling-in.

A further suggestion to avoid this eversion is to manufacture a linerhaving an inner coating and an cuter coating so that a curing fluid canbe introduced directly into a pulled-in liner. The disadvantages hereinvolves the difficulty faced when trying to impregnate the resinimpregnable material disposed between the inner and outer impermeablecoatings The outer coating remains essential for handling theimpregnated liner and to allow the liner to be pulled into the existingconduit and the inner coating is desired to all for curing with thesteam.

Notwithstanding the modifications to both the eversion and pull-in andinflate trenchless rehabilitation methods, both processes are laborintensive, require an eversion step and suffer from tie increased costsassociated with this. Accordingly, it is desirable to provide arehabilitation method utilizing pull-in and inflate methodology whereinthe liner is manufactured with an inner and outer coatings and readilyimpregnated so that it can be cured by steam as the curing fluid to takeadvantage of the energy available to provide an installation methodwhich is faster and more efficient economically than currentrehabilitation methods.

SUMMARY OF THE INVENTION

Generally speaking, in accordance with the invention, a resinimpregnated cured in place liner with an integral inner impermeablelayer suitable for pull-in and inflate rehabilitation of existingpipelines is provided. The liner is continuously formed from a length ofresin absorbent material having bonded thereto on one surface animpermeable layer formed into a tubular shape and sealed into a tubewith the impermeable layer on the inside of the tube. The resinabsorbent tube with the inner impermeable layer may be wrapped withadditional layers of resin absorbent material secured into tubular form.An impermeable film is wrapped about the inner resin impregnable tube.The resin absorbent material may be impregnated with a thermosettingresin before or after the outer resin impermeable film is wrapped aboutthe inner tube.

The inner impermeable layer should be one which is resistant to the hightemperatures of the curing fluid and exposure to fluids intended to becarried with in the rehabilitated pipe. The outer layer may be simplyheat sealed using a thermal bond or taped. This outer seal merelyencapsulates the resin impregnated material but should have sufficientstrength to withstand handling and abrasion as the liner is transportedand then pulled into the existing conduit.

The resin absorbent material with the integral impermeable layer on onesurface can be formed into a tube and sealed in a variety of ways. Thisincludes conventional heat bonding and taping, sewing and taping, orsealing with an extruded material. The tube is continuously formed withthe resin impregnable layer on the inside about a tubular device in onedirection with the impermeable layer on the outside, sealed in aconventional manner and then everted continuously through the formingdevice. The outer layer is now the resin absorbent layer or layers thatare impregnated prior to or after being wrapped with a polymeric coatingto contain the resin and allow for storage and pulling the liner withinner and outer impermeable layers into the existing conduit.

Accordingly, it is an object of the invention to provide an improvedmethod of cured-in-place rehabilitation of existing pipelines.

Another object of the invention is to provide an improved liner forcured in place rehabilitation of an existing pipeline.

A further object of the invention is to provide an improved liner havingan integral inner impermeable layer suitable for trenchlessrehabilitation of existing pipelines.

Yet another object of the invention is provide an improved method ofcontinuously manufacturing a resin impregnated cured in place linerhaving an integral inner impermeable layer.

Yet a further object of the invention is to provide a method ofmanufacturing a resin impregnated cured in place liner having anintegral inner impermeable layers and an outer impermeable coating forpull-in and inflate trenchless pipeline installation.

Still other objects and advantages of the invention will in part beobvious and will in part be apparent from the specification.

The invention accordingly comprises the several steps and the relationof one or more of such steps with respect to each of the others, theapparatuses embodying features of construction, combinations andarrangement of parts that are adapted to effect such steps, and theproducts that possess the characteristics, features, properties, and therelation of components, which are exemplified in the following detaileddisclosure, and the scope of the invention will be indicated in theclaims.

BRIEF DESCRIPTION OF THE DRAWINGS

For a fuller understanding of the invention, reference is had to thefollowing description taken in connection with the accompanyingdrawing(s), in which:

FIG. 1 is a Perspective view of a length of a typical resin impregnablecured in place liner suitable for use in lining an existing pipeline ofthe type generally in use today and well known in the art;

FIG. 2 is a cross-section view of a cured in place liner having anintegral inner impermeable layer and an outer impermeable film orwrapping constructed and arranged in accordance with the invention;

FIG. 3 is a schematic view of the apparatus used for preparing the innerportion of the liner having an outer felt layer with an integral innerhigh temperature polymeric layer used in connection with preparation ofthe cured in place liner of FIG. 2;

FIG. 4 is a cross-sectional view showing the structure of the innertubular portion of the liner produced by the apparatus of FIG. 3;

FIG. 5 is a schematic in elevation showing resin impregnation andwrapping of the tubular member of FIG. 4 for preparing an impregnatedCIPP liner having inner and outer impermeable layers in accordance withthe invention;

FIG. 6 is a cross-sectional view of the edge sealing device of thewrapping apparatus of FIG. 5 taken along line 6-6; and

FIG. 7 is a cross-section of the liner prepared by the apparatus ofFIGS. 3 and 5.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

A resin impregnated cured in place liner prepared in accordance with theinvention has an integral internal lining so that it can be installed bythe pull-in-and-inflate method and inflated and cured with a heatedfluid without the use of an inflation bladder. The impregnated linerwith inner impermeable polymer layer is prepared continuously in desiredlengths. The liner may be impregnated as it is assembled in view of theincreased effort necessary to impregnate a flattened liner having aresin absorbent material between an inner and an outer coating usingconvention vacuum impregnation technology.

This increased effort necessary is evidenced by the process suggested inU.S. Pat. No. 6,270,289. Here, above ground a calibration hose isinverted into a flat-lying impregnated lining hose, or an impregnatedlining hose is inverted into a tubular film using compressed air. Inthis case, the length of the lining hose approximates the length of theunderground conduit to be lined. The inversion of one tube inside theother requires an unobstructed length equal to the length of the longestlayer. If the two layers had not been previously impregnated, it wouldbe necessary to inject resin between the layers on both sides of the layflat tubes in order to provide adequate impregnation. This is adifficult and inefficient way to impregnate lining tubes. Thus, not onlyis the length restricted, but also the impregnation is extremelydifficult.

FIG. 1 illustrates a flexible cured in place liner 11 of the typegenerally in use today and well known in the art. Liner 11 is formedfrom at least one layer of a flexible resin impregnable material, suchas a felt layer 12 having an outer impermeable polymer film layer 13.Felt layer 12 and outer polymer layer 13 are stitched along a seam line14 to form a tubular liner. A compatible thermoplastic film in a form ofa tape or extruded material 16 is placed on or extruded over seam line14 in order to ensure the impermeability of liner 11. In the embodimentillustrated in FIG. 1 and used throughout this description, liner 11includes an inner tube of a second felt layer 17 also stitched along aseam line 18 positioned at a point in the tube other than the locationof seam line 14 in outer felt layer 12. Outer felt layer 12 with polymerlayer 13 is then formed around inner tubular layer 17 After impregnationliner 11 in a continuous length is stored in a refrigeration unit tosuppress premature cure of the resin. Liner 11 is then cut to a desiredlength after being pulled into the existing pipeline, or is cut prior tobeing everted into the existing pipeline.

Liner 11 of the type illustrated in FIG. 1 is impermeable to water andair. This will allow use in an air or water eversion as described above.However, in a pull in and inflate installation in accordance with theinvention, the outer coating on the liner need only be sufficiently inpermeable to allow for suitable wet out and retention of resin and toprevent damage to the liner as it is pulled into the existing pipeline.

For larger liner diameters, several layers of felt or resin impregnablematerial may be used. Felt layers 12 and 17 may be natural or syntheticflexible resin absorbable material, such as polyester, acrylicpolypropylene, or inorganic fibers such as glass and carbon.Alternatively, the resin absorbent material may be a foam. Impermeablefilm 13 in outer impermeable layer 12 may be a polyolefin, such aspolyethylene or polypropylene, a vinyl polymer, such as polyvinylchloride, or a polyurethane as is well known in the art. Any form ofsewing, adhesive bonding or flame bonding, or any other convenient meanscan be used to join the material into tubes. In the initial step in alltrenchless rehabilitation installations, the existing pipeline isprepared by cleaning and videotaping.

Referring now to FIG. 2, a cured in place liner 21 prepared inaccordance with the invention is shown in cross-section. Liner 21 isconstructed in similar fashion to convention liner 11, but includes aninner tubular member with an integral inner impermeable layer 22 thathas a thin felt or resin impregnable layer 23 bonded thereto. Inner feltlayer 23 with impermeable layer 22 has been sewn along abuttinglongitudinal edges to form a seam line 24 by a row of stitches 26 andsealed with a tape 27 applied over stitches 26. An outer felt layer 28is wrapped about inner thin felt layer 23 and formed into a tube bystitches 29. Finally, an outer layer or wrapping 31 is disposed aboutouter felt layer 28.

By providing a liner having both inner and outer impermeable layers, itis not necessary to evert the liner during installation or evert aninflation bladder after the liner has been pulled into the existingconduit. Thus, significant saving in labor cost at the time ofinstallation are available. It also allows for use of a heated curingfluid such as steam to inflate and cure the resin. In such case all theheated fluids are introduced into the liner below ground level toprovide a safer work environment.

Felt layers 23 and 28 may be impregnated in the usual manner usingvacuum. Alternatively, felt layers 23 and 28 are first impregnated withresin and then an outer impermeable wrapping 31 is applied. This avoidsthe difficulty with impregnating a finished liner having felt layersbetween an inner and outer impregnable layer. In U.S. Pat. No.4,009,063, Eric Wood proposed injecting resin in the felt layer usingneedles inserted into opposite sides of a flattened constructed liner.This operation requires cutting and patching needle holes in the outercoating. The vacuum impregnation process taught in U.S. Pat. No.4,366,012 would not be suitable unless the vacuum is drawn on both sidesas the inner coating is a barrier to resin flow in a liner with innerand outer coating. In order to overcome these impregnation difficulties,liner 21 is manufactured from endless rolls of flat coated and plainfelt and continuously impregnated prior to application of outer wrapping31. This is accomplished by the method illustrated in FIGS. 3 and 5resulting in a liner 68 as illustrated in FIG. 7.

While felt layers 23 and 28 are formed into tubes by stitching and/ortaping, any of the conventionally known methods for forming felt orother resin impregnable material into tubes is suitable. For example,tubes can be formed by use of various glues or adhesives as well asflame bonding. Tape may be applied to inner felt layer 23 and innerimpermeable layer 22 by applying an adhesive strip, extruding a layer ofpolymeric material, or heat fusing the tape in order to seal the buttededges of the felt material and the holes formed during a sewingoperation.

Referring now to FIG. 3, a method for continuously forming a length of atube of resin impregnable material with a sealed inner layer ofimpermeable material is shown. A roll of coated felt 36 having anendless length of felt 37 with an impermeable layer 38 bonded to onesurface is fed over a directional roller 39 in flat form with coatedside facing roller 39 to a tube-forming device 41.

Tube forming device 41 includes a tubular support frame 42 having aproximal end 42 a and a distal end 42 b and a film deformer 40. Aseaming device 43 that may be a sewing and taping machine, gluingmachine or flame bonding apparatus is mounted above support frame 42.Felt 37 with impermeable layer 38 facing roller 39 is fed in thedirection of an arrow A to the proximal end of tube forming device 41where it is deflected by deflector 40 and wrapped around support frame42 and seamed into a tube 44 along a seam line 46 with felt 37 on theinside and impermeable layer 38 on the outside. Tube 44 then passes ataping device 47 where a tape 48 is placed over seam line 46 to form animpermeable coated taped tube member 45.

Taped tube member 45 then continues to travel along tubular supportframe 42 to an inverter ring 49 at the distal end 42 b of support frame42. Taped tube member 45 is then everted into tubular support frame 42so that impermeable layer 38 is now on the inside of tube 45 as it iswithdrawn from the proximal end 42 a of tubular support frame 42 along aline defined by an arrow B. At this point everted tube 45 has thestructure illustrated in cross-section in FIG. 4 with impermeable layer38 on the inside of tube 45 and felt layer 37 on the outside. Tube 45then continues to travel in the direction of arrow B for the addition ofone or more plain felt layers. Tube 45 is then stored for further use,wrapped with an outer impermeable coating, or may be passed directly toa resin impregnation step as shown on FIG. 5 prior to final wrapping.

FIG. 5 illustrates in schematic impregnation of a supply 51 of tapedtube 45. Here, tube 45 is pulled in arrow direction C by or through apair of rubber covered pulling rollers 52 into an open top resin tank 53filled to a predetermined level with a curable thermoset resin 54 toform an impregnated or wet out tube 55. Tube 45 passes between a firstand second set of compression rollers 56 and 57 and around a firstdirectional roller 58 to turn tube 45 in a horizontal direction and asecond directional roller 59 to turn tube to a vertical direction. Asonic wave generator 61 may be utilized in lieu of or in addition tosecond compression rollers 57. Sonic wave generator 61 improves theimpregnation of resin 54 into felt layer 37 of tube 45 as it passesthrough resin tank 53. After changing direction about second directionalroller 59, impregnated tube 55 passes between a pair of pneumaticcalibration rollers 62. At this time, tube 55 then enters through a filmwrapping and sealing station 63.

Wrapping and sealing station 63 includes a roll 64 of a resinimpermeable film material 66 that is wrapped about moving impregnatedtube 55 as it passes into a film edge sealer device 67. Resinimpregnated tube 55 is now a wrapped tube 68 having an impermeable outerwrapping 69 with an edge seal 71 as it exits film edge sealer 67 asshown in cross-section in FIG. 7. Wrapped tube 68 is pulled by a pair offinal pulling rollers 72 and fed along an arrow D as shown in FIG. 5 toa refrigerated truck for shipment to an installation site.

FIG. 6 is a cross-sectional view of edge sealing device 63 showing film66 formed into a sealed tube 69 of impermeable film 66 with a sealededge 71.

FIG. 7 is a cross-sectional view of the finished wrapped tube 68 withimpregnable layer 37 and integral inner impermeable layer 38 bondedthereto and outer wrapping 69. As noted in connection with liner 21 inFIG. 2, there may be more than one layer of resin impregnable, dependingon the diameter or engineering requirements of the installation.

Once at the installation site, impregnated tube 68 having innerimpermeable layer 38 and outer impermeable wrapping 69 is ready forinstallation by the pull-in-and-inflate method. This method is fullydescribed in U.S. Pat. No. 4,009,063, the contents of which areincorporated herein by reference. In the case of installation by thepull-in-and-inflate method, a separate eversion bladder is not necessaryto inflate the liner due to the presence of integral inner impermeablelayer 38. By proper selection of materials for integral innerimpermeable layer 38, such as polypropylene, inflation and curing can bedone with steam introduced into the liner 68 once in position in theexisting conduit.

The processes and apparatuses described herein provide a convenientmeans to prepare a cured in place liner having an inner impermeablelayer and an outer impermeable film. A tube forming and eversionapparatus as illustrated in FIG. 3 readily provides a method to preparethe inner portion of the finished tube with a sealed impermeable layeron the inside of the tube and an outer felt or resin impregnable layer.Additional layers of uncoated felt may be wrapped about the formed innertube if desired.

The tube prepared in accordance with the process described in connectionwith FIG. 3 is then readily impregnated in an open top resin tank andwrapped with an impermeable wrapping as described in connection with theapparatus shown in FIG. 5. Use of an open resin tank and compressionrollers avoids the need to impregnate utilizing high pressure techniqueswhich are cumbersome to use in view of the desire to impregnate in acontinuous fashion. Alternatively, if the liner is wrapped prior toresin impregnation, the liner can be wet out by vacuum in the usualmanner as noted above.

It will thus be seen that the objects set forth above, among those madeapparent from the preceding description, are efficiently attained and,since certain changes may be made in carrying out the above process, inthe described product, and in the construction(s) set forth withoutdeparting from the spirit and scope of the invention, it is intendedthat all matter contained in the above description and shown in theaccompanying drawing(s) shall be interpreted as illustrative and not ina limiting sense.

It is also to be understood that the following claims are intended tocover all of the generic and specific features of the invention hereindescribed and all statements of the scope of the invention which, as amatter of language, might be said to fall therebetween.

1. A continuous length of a cured in place liner having at least one layer of resin impregnable material and an impermeable layer bonded thereto, comprising a liner formed by providing a length of a resin impregnable material having an impermeable layer bonded to one surface and formed into a tube about a support frame with the impermeable layer on the outside; the longitudinal edges of the length of material joined together about the support frame and sealed to form a tubular member that is everted through the support frame so that the outer layer of the liner is the resin impregnable material.
 2. The liner of claim 1, including at least one additional layer of resin impregnable material about the layer of resin impregnable material.
 3. The liner of claim 1, wherein the tubular member is impregnated with resin.
 4. The liner of claim 1, wherein the length of resin impregnable material is formed into tubular members by stitching the longitudinal edges.
 5. The liner of claim 1, wherein the tubular member is sealed by applying a tape of impermeable material over the longitudinal edges.
 6. The liner of claim 3, further including a layer of impermeable material sealed about the impregnated tubular member.
 7. The liner of claim 1, wherein the tubular member is impregnated with resin.
 8. The liner of claim 7, further including a layer of impermeable material sealed about the impregnated tubular member.
 9. A continuous length of a cured in place liner having at least one layer of resin impregnable material and an impermeable layer bonded thereto, comprising a liner formed by providing a length of a resin impregnable material having an impermeable layer bonded to one surface and formed into a tube about a tubular support with the impermeable layer on he outside; the longitudinal edges of the length of material joined together about the tubular support and sealed to Form a tubular member that is everted through the tubular support so that the outer layer of the liner is the resin impregnable material, and the tubular member is impregnated with resin and a layer of impermeable material sealed about the impregnated tubular member. 